Hi Heinrich,
We're moving away from YUI and upgrading jQuery on a "as-needed" basis. At this point, we're not actively working on getting rid of all YUI code, "just for the sake of it", but are doing it piece by piece, when it looks like the benefits of such a move are higher than the risks.
Did you have a particular situation in mind where YUI is a problem? Or that would call for a more recent version of jQuery?
Alex
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